1. Technical Field
The disclosure generally relates to a backlight module, and especially relates to a backlight module with fewer light sources, wherein each light source includes laser emitters.
2. Description of Related Art
In recent years, due to excellent light quality and high luminous efficiency, light emitting diodes (LEDs) have increasingly been used as substitutes for incandescent bulbs, compact fluorescent lamps and fluorescent tubes as light sources of illumination devices.
Light emitting diodes can be used as light sources in a direct-type LED backlight module. Generally, the light emitting diodes are arranged in a matrix, secondary optical lenses are located over the light emitting diodes for increasing the emitting angles of the light beams from the LEDs and a diffusing plate is located over the secondary optical lens for uniformly mixing the light beams from the secondary optical lens, whereby the light beams can be uniformly output to illuminate an LCD (light crystal display). However, in the direct-type LED backlight module described above, the number of the light emitting diodes is relatively huge, thereby increasing the cost of the direct-type LED backlight module.
What is needed, therefore, is a backlight module to overcome the above described disadvantages.